Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
108 PM EST Sat Dec 7 2013
high pressure will build into the region today...before moving off
to the east tonight. Another weather system will bring more
wintry precipitation Sunday into Sunday night...but it will lift
to the northeast of the region on Monday.
Near term /until 6 PM this evening/...
an Arctic high pressure system will build over the Great Lakes
today. Some low level moisture continues to linger near the Ohio
River and near our northwest zones...so have skies becoming partly cloudy
in these areas with mostly sunny skies elsewhere.
Temperatures will see little rebound today as an unseasonably cold
airmass filters into the region. Highs will be in the lower to middle
20s for much of the region...with some upper 20s to around 30 in
Short term /6 PM this evening through Monday/...
another wave of energy will race quickly into the region tonight in
the broad SW flow aloft. Precipitation will be pulled northward through Kentucky along an
inverted surface trough. This precipitation will encounter the Arctic airmass
that settled across the region Saturday night.
Model soundings are showing that the precipitation will start as snow late
tonight in NE Kentucky and then into southern Ohio and southeast Indiana Sunday
morning...before reaching west central Ohio later in the morning.
As warmer air aloft is pulled in on Sunday...a change to sleet and
freezing rain will occur. In the southeast counties a change to liquid
rain is expected during the afternoon. This sets up the best area of
icing from cmh over to day and cvg where around a tenth of an inch
of ice is possible. Overall an inch or two of snow is possible
with the system.
Cooler air will be pulled back into the region Sunday evening as a
weak surface reflection works to the north. This cause a change over the
wintry precipitation again Sunday night. Therefore have issued a Winter
Weather Advisory for Sunday and Sunday night for all but west
Lows tonight will be in the teens for most locations with clear
skies and a fresh snow pack early...but then increasing clouds
with sundays storm system. Southern locations could see rising
temperatures after midnight. Highs Sunday will only be in the upper
20s in the northwest half of the forecast area...with the southeast counties making the middle 30s.
Highs on Monday in the wake of the system will be in the 30s.
Long term /Monday night through Saturday/...
behind another cold front...most of next week appears dry but
frigid. Raw model temperatures are certainly influenced by an
expected snow pack...thus the resulting forecast numbers will
probably be able to be improved more significantly after the
current storm is finished and the snow pack is laid out. Sorting
through the usual assortment of raw min temperature bullseyes (well into
negative numbers)...the overall temperature forecast has held
mostly steady since yesterday...giving confidence in a cold week
(with single-digit lows across The Heart of the cwa). While
temperatures should eventually get (barely) above freezing for
most of the iln County Warning Area early on Monday...sub-freezing temperatures are
forecast for the next four days straight...even for maxes. A
slight moderating trend will begin on Friday...perhaps lasting
into the weekend.
Aviation /18z Saturday through Thursday/...
Arctic high pressure centered over the Great Lakes this afternoon
will move off to the northeast through tonight. Meanwhile...energy
in a buckling SW flow aloft will induce an inverted trough in the
Ohio Valley on Sunday. This process will result in warm...moist
advection over the cold air in place across the region. Thus...light
precipitation should develop to our southwest tonight...and push
northeast across the taf sites on Sunday. Atmospheric column will
saturate and snow will be the main ptype first...transitioning
over to light sleet and freezing rain to light freezing rain
and/or light freezing drizzle in the afternoon. Ceilings will drop
into the IFR/LIFR range while visibilities drop into the IFR range
associated with light precipitation.
Outlook...LIFR ceilings and visibilities likely Sunday night into
Monday. These conditions will transition to MVFR ceilings Monday
Ohio...Winter Weather Advisory from 6 am Sunday to 4 am EST Monday
Kentucky...Winter Weather Advisory from 6 am Sunday to 4 am EST Monday
In...Winter Weather Advisory from 6 am Sunday to 4 am EST Monday